APPENDIX. 425 



Genus GRAMMATOPHOBA belongs to the Bacillaria, 

 section Naviculaceae. The members have a simple bivalved 

 prismatic siliceous lorica, and are unattached. Self- 

 division is imperfect, and the cluster curved, the joints 

 gaping at one of the angles. Within are generally seen 

 two undulated folds, dividing the body into three longi- 

 tudinal portions. 



740. GRAMMATOPHORA Africana. Wands, when viewed 

 dorsally, square or oblong; from the side,|Navicula-like (boat- 

 shaped), and obtuse. Internal folds three, and undulated. 

 Found, fossil, in the chalk marl of Oran, and alive, in sea 

 water, at Tjorn. The live creature has brownish, or golden- 

 yellow-coloured ova, filling the whole of the interior, and 

 only leaving a bright transverse band empty just where 

 the transverse tube goes through the body. Length 

 l-2300thto 1 -480th. 



741. GRAMMATOPHORA angulosa. Wands, when 

 viewed dorsally, square or oblong ; from the side, Navicula- 

 like, and obtuse ; internal fold having many acute angles. 

 It is not very certain whether this species is only a 

 variety of the preceding. Found fossil in the chalk 

 marl of Oran, and alive, in sea water, at Tjbrn. The crea- 

 ture is colourless. Length of fossil 1-9 10th; the living, 

 1-1 150th. 



742. GRAMMATOPHORA Mexicana. Wands, when 

 viewed dorsally, quadrangular; from the side, linear, obtuse, 

 the ends being suddenly constricted. Internal folds straight 

 in the middle, uncinate at the extremity. Found alive, in 

 sea water, at Vera Cruz. Length 1 -960th, and little more 

 than twice its breadth. 



743. GRAMMATOPHORA oceanica. Wands, viewed dor- 

 sally, quadrangular ; from the side, navicular, or linear, 

 obtuse, but the ends gradually attenuated ; internal folds 

 straight in the middle, uncinate towards the ends. Found 

 fossil in the chalk marl of Oran, alive in the waters of the 



